Method of and apparatus for burning solid fuel



F. NOVELLI April 29, 1930.

\ METHOD OF AND APPARATUS FOR BURNING SOLID FUEL Filed May 21, 1927 I I I IIIIJ Patented Apr. 29, 1930 PATENT orrir.

FRANCESCO NOVE LLI, OF PESCINA, ITALY METHOD on m: ArrArtawvs roa BURNING SOLID FUEL Application filed May 21, 1927, Serial No. 193,153, and in Italy May 27, 1926.

The present invention concerns a novel combustion process applicable to all the heating, cooking and melting furnaces, as for instance furnaces for steam boilers, for bricks,

earthenwares, lime, and glass ovens and the like wherein is burnt pitcoal, lignite or similar combustibles adapted to be gasified.

According to my improved process, in order to obtain best thermal efficiency from the fuel burnt, all the gaseous constituents are first burnt and then the solid residue either wholly or in part.

WVith the said object in view I introduce into the combustion chamber of the furnace retorts, filled with the combustible, which retorts may be placed vertically, horizontally or in an inclined position according to the particular requirements; said retorts are provided with holes in their walls through which go the gaseous distillationproducts of the combustible can escape.

Theoperation is started by a preliminary heating effected with any convenient fuel outsideof the retorts and in such quantity as will suffice for initiating the distillation of the combustible contained in the retorts. lVhen the distillation has begun, the gases which escape from the holes in the walls of the retorts take fire and burn in the furnace thereby furnishing the heat required for the action of the furnace and also insuring the distillation, so that no other extraneous fuel is required for obtaining the reduction coke of the combustible contained in the retorts. At this point the combustion can be stopped, when the coke obtained may be otherwise utilized, or even sold with profit, and in that case, the number and the size of the retorts must be so selected that the operation to be performed by the oven be completed at the end of the distillation. If, on the contrary, the work of the oven is continuous, means must be provided for the change or reloading of the retorts at the end of the distillation.

When the coke thus obtained cannot be otherwise employed it may be, wholly or at least partly, burnt in the same retorts wherein the distillation has been effected.

For this purpose the number, the arrangement and the size of the holes provided in the walls of the retorts as well as the volume of the air admitted and the time of this admission are regulated in such a manner that, when the generation of the gases has stopped, the combustion of the coke within the retorts is established by means of the air current which enters through said holes into the retorts.

By leaving at the end of the operation a to certain quantity of coke unburnt, one can utilize this residual quantity in a subsequent operation for starting the combustion in the manner above explained.

By way of example I have shown on the annexed drawing a brick furnace of the Hofmann type adapted to operate in accordance with the present invention, and in said draw- 111 Figures 1 and'2 show a vertical cross section of the furnace and, partly, a longitudinal section thereof Fig. 1 being a section along line II in Fig. :2, and Fig. 2 a section along line IIII in Fig. 1, while Figure 3 shows a structuraldetail.

In the well known type of brick furnaces the fuel is introduced into the combustion chamber by letting it drop through charging holes 12 provided in the roof of the furnace.

In the furnace according to'this invention I provide, under the said charging holes, cylindrical retorts 2 comprising a suitable number of sections of refractory material. At their upper end said retorts are each provided with a removable'cover 8 and in their peripheric walls with a numberof holes Through their lower open end they communicats with a horizontal fine 5 extending under the bottom of the chamber 1 in a direction contrary to the progress of the fire and opening at 10 a certain distance from the bottom of the chamber 1. The retorts containing pit coal, lignite or similar combustibles need not be placed under allthe chargingholes 12.

After the retorts have been completely. or partly, filled with combustible (according as it is desired to bake in a single operation a larger or a lesser quantity of bricks, it being besides very easy to introduce more coal into the retorts even when the combustion is l fully running) and the retorts become incanately ignite.

- descent, the coal contained therein begins to distill, the combustion gases escape through the'holes 4c and the lower outlets and nnrnedr Tests, many, times repeated, have shown that, Without a change 111 the size and the other arrangements of the usual furnaces the 1 heatin can be effected onl b means of the b gaseous portion of the fuel, leaving in the retorts a quantity of coke Which amounts to about 80% in Weight of the coal shared into the retorts. V 1

The coke thus obtained can be utilized for any desired purpose. When there are no spondence With certain of said charging holes whereby fuel may be introduced through the remaining charging holes for heatin said retorts, said retorts having perforations in their Walls, a gas passage provided at the'lower end F,

' facilities for utilizing'it for other purposes 5 a 4 audit 18211013 COIlVGlllGnttD-sBlllt, the quantity 7 V oflgcoal-introduced into the retorts, the num-Z leer, the'arrangement and theslzeof the holes 7 51:

.which' reaches the interiorof the retorts wthroughithe holes in-their Walls.

providedin-the walls of the retorts for the escape-of thegases, and' the quantity of the air admitted to-the furnace are regulated in n suchmannertthatatthe-end of the distillation the coke produced begins to burn in its turn,

itsgcombustion being sustained by the air Thusjisiutilized on the spot not only theentire heat of combustion ef the gaseousportion of the-fuel, which upxto day has been main- V ly lost butals tand completely,the heat of combustionsof the-solid portion, and this complete'utilizat'ioir of the fuel is obtained in the I 7 best and most convenient manner, in that either, the. :Coke is burnt Within the retorts v :Whenoiniit has; been produced, or it is burnt inthe furnace between the retorts.

The furnace is completed by the channel 7 which serves forthe exhaust of thesmoke through the funnel Sand-the manholes 9 of the furl-llowever inany case, in order to obtain the aresultxdesined, the quantity of the air to be ysnpplied,;by"any convenient means'most suitable for the particular kind of furnace, must be nicely adjusted for sustaining the combustion in the manner prescribed Without being in excess or deficient.

It will be apparentthat this improved method of combustio-nis suitable not only for brick, earthenwareand limefurnaces but also for all those furnaces in theeombustion chambers, of wh ch, (or in adyoiningxauxiliary chambers) it is possible .to place distillationretorts, and it is, also 'apparentthat in said, furnaces either between the retorts or upon specially prepared grates it is'possible to effect together with. the combustion of the gases escaping from the retorts, the [combust-ion of the coke obta'ined'insame;

I claim:

A furnace comprising aconibustion chamr her having inits topa pluralityof charging holes having removable covers, vertical, tu-

b llai retortsdisposedxbeneath and in corre- 

